Circuit control



Oct. 20, 1931. HESSE- 1,828,321

CIRCUIT CONTROL Filed March l1, 1929 Lfijzfd H5555 Patented Oct. 210, 1931 UNITED STATES LEONARD HESSE, F PLYMOUTH, WISCONSIN CIRCUIT CONTBI Applicationl led March 11, 1929. Serial No. 346,051.

This invention pertains to circuit controls, and has primarily for its object the provision of a simple and efficient arrangement for controlling an electric circuit in such manner that the circuit will remain operative for a predetermined length of time after the main control switch has been opened.

Incidental to the foregoing, a more specific object is to provide a control of the foregoing character, which is thermostatically actuated.

A still further object of the invention resides in the provision of a control of the foregoing character in which means is provided for varying the period of time required for operation.

With the above and other objects in view, which will appear as the description proceeds, the invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described and more particularly defined byl the appended claim, it being understood that such changes in the precise embodiment of the herein disclosed invention may be made asv come within the scope of the claim.

In the accompanying drawings is illustrated one complete example of the physical embodiment of the present invention constructed according to the best mode so far devised for the practical application of the principles thereof In the drawings, Figure 1 is a plan view of the invention, with parts broken away to more clearly illustrate structural details of the actuating mechanism;

Figure 2 is a longitudinal section taken on the line 2 2 of Figure 1, and

Figure 3 is a diagram of a typical circuit m employed in combination with the controlling device.

The present invention, which is designed primarily to maintain the operativeness of an electric circuit for a predetermined period r of time after the main control switch has been opened, is particularly applicable to the lighting circuits of residences, oiiices, and 'the like, in which it is desired to maintain a l light for a predeterminedperiod after the P0 switch is thrown off, to permit suicient time for exit or other purposes, prior to extinguishing the light.

Referring now more particularly to the accompanying drawings, the numeral 10 designates a receptacle for housing the actuating mechanism, and is provided with a removable cover plate 11 held in position by suitable securing mediums, such as the screws 12 that extend through the edge portion of the cover 11 into the flange portions 13 pro- 60 vided in the receptacle 10.

Suitable openings 10 are provided in the receptacle to permit insertion of the wiring comprising the electrical circuits. Obviously, the receptacle 10 may be constructed in 65 accordance with any type 'of conventional receptacle now on the market, which provides for the connection of'a liexible or other type conduit.

Spaced from the rear wall 14 of the hous- 70 ing 10 is a supporting plate 15. The supporting plate 15 is retained in position by the bolt and nut construction 16 which ex tend through spaced washers such as 17. Arranged-on the supporting plate 15, in a position substantially similar to that indicated in Figure 1, is a substantially L-shaped bracket 18, which has the portion 19 thereof varranged at right angles with respect to the plate 15. Another substantially L-shaped SQ bracket 2() is mountedl on the plate 15 in spaced relation with the bracket 18, and the portion 21 of this bracket is arranged at right angles with respect to the plate 15. l Extending from the portion 19 and se- 85 cured thereto, is a thermostat-ic member 22 which is formed from two co-extensive strips of dilferent metals. -One of these strips is indicated by 23 in the drawings and, by way of example, this strip may be made from iron.v The other strip is indicated by 24 in the drawings and, by way of example, this strip may be made from brass. The strips 23 and 24 are suitably secured together at intervals throughout their lengths by any suit- 9-5 able means such as by rivets 25. The free end portion of the thermostatic member 22 i's bent in the manner illustrated in Figure 1, such that the tliermostatic member 22 will be formed substantially J-shaped ma for a purpose to be set out hereinafter. On the free end of the thermostatic member 22, I arrange a contact 26 which is adapted to cooperate with a contact post 27 mounted in the portion 21 of thebracket 20. The contact post 27 is preferably in the form of a screw and has screw threaded engagement with the portion 21 and is held in predetermined positions by the lock nut 28.

Disposed around the thermostatic member 22 is a coil of resistance wire 29, which is preferably wound so as to avoidA self-inductance, and one end of this resistance wire 29 is connected to the thermostatic member 22, as indicated at 30, and the other end of this resistance wire 29 is connected to the binding post 31 mounted on the strip 32. A strip 33 is mounted on the plate 15 and has a clip structure 34 provided thereon. Cooperating with the clip structure 34 is a clip structure 35 carried by the bracket 20, and a resistance 3.6 in the form of a cartridge is removably mounted in these clips.

The brackets 18 and 20 and the strips 32 and 33 are preferably insulated from the plate 15. A fibre sheet 20 can be interposed between the brackets 18 and 20 and the supporting plate 15. A binding post 37' is ar.- ranged on the strip 33 and a binding post 38 is provided on the strip 32. Arranged intermediate these binding posts is a switch structure 39 which may be of any desired form and which is preferably mounted extraneous of the housing 10.

The connections employed for interconnecting the various operating mechanisms of my device are as follows: .n

Leads 40 and 41 are directed to a suitable source of current and the lead 40 is directed to the binding post 37 so that passage therethrough ,will be controlled by the switch 39. The lead 41 is connected to a terminal 42 of a lamp structure 43. A conductor 44 is connected to a terminal 45 of the lamp struc ture 43, and is connected to the thermostatic member 22.

In operation, the current flows through the conductor 40, binding post 37, switch 39, binding post 38, to terminal 31, thence through resistance coil 29, to the connection 30 and thence through the thermostatic member 22 to lead 44, to terminal 45 through the filament of the lamp 43 to terminal 42 and thence through conductor 41. In this manner, the lamp 43 is rendered operative.

The current flowing through the resistance coil' 29 will tend to heat the thermostatic memberl 22, and, due to the fact that this thermostatic member is comprised of strips having different coeilicients of expansion, the curved end portionof said member will be caused to move outwardly, and thus the contact 26 will be 'moved into engagement with the contact post 2,7. The contact post 27 is connected by a lead 46 to the clip 35.

The clip 34 is connected by a lead 47 to the binding post 37 and it has been pointed out that the resistance 36 interconnects these clips. The resistance 36 is arranged so as'to have an ohmic resistance greater than the ohmic resistance of the resistance :coil 29 and, therefore, current will flow through the previously described circuit as long as the switch 39 remains closed. However, when the switch is opened, current will no longer flow through the resistance coil 29 and, therefore, the thermostatic member 22 will be permitted to cool at a predetermined time, dependent upon the position of the contact post 27, the contact 26 will disengage said contact post 27 but durin the interval between the disengagement of t e contacts 26 and 27 current will still be supplied to the filament of the lamp 43 throu h a circuit including the conductor 40, bin ing post 37, conductor 47, clip 34, resistance 36, clip 35, conductor 46, contact post 27, contact 26, thermostatic member 22, and the conductor 44 and through the elements hereintofore set forth to llluminate the lamp\43.

It is readily apparent that by varying the position ofthe contact post 27 the time at which the contact 26 will disengage this post may be greatly varied, and in this manner the length of time that the lamp 43 will operate after the switch 39 is opened, may be varied. While I have shown the lamp 43 as being controlled in the manner hereintofore set forth, it is apparent that any described electrically operated apparatus may 10o be substitutedk for the lamp 43, without de parting from the purview ofmy invention.

From the foregoing description, taken in connection with the drawings, it will be seen that a main circuit has been provided, comprising the leads 41 and 40, which are connected through the thermostatic element 22, the resistance coil 29, and the control switch 39, while the wires 46 and 47, connected through the resistance 36, form an auxilia- 11 ry or shunt circuit, through which the c urrent will pass for a predetermined perlod after the main circuit has been opened.

I claim:

In a delayed circuit control, a housing, a supporting plate in said housing, a pair of spaced angle-shaped brackets secured to the plate on opposite sides of the longitudinal center of said plate, a substantially J-shaped thermostatic member arranged in the hous- 1z0 ing including a relatively long leg and a relatively short leg, the vthermostatic member including layers of metal of different coefficients of expansion, each of said angle plates constituting binding posts, one end of said thermostatic member being rigidly secured to one of the angle brackets, an adjustable contact secured to the other angle end of the short leg of the thermostatic mem' ber, a Contact plate secured to the supporting plate intermediate the angle brackets, and a heating coil around said member having one 5 end connected to the thermostatic member and its opposite end to said Contact plate.

In testimony that I kclaim the foregoing I have hereunto set my vhand at Plymouth, in

the county of Sheboygan and State of Wism cousin'.

LEONARD HESSE. 

